Francesca’s F1 Kayak, Seattle, WA

My Kayak 

I’m a thirteen year old living in Seattle and I built my own kayak. It’s a skin-on-frame F1 designed by Brian Schulz of Cape Falcon Kayak and I made it in our driveway. In the beginning, I was skeptical I could build a boat but it wasn’t as hard as I thought. Although my dad gave me advice and showed me how to use the power tools, I did all the steps myself. 

Before I made the kayak I already had some woodworking skills. For example, over the last year or two I built a horse jump with my friend, rustic cedar planter boxes with my school and wooden marlin spikes for nautical ropework. I made the Greenland kayak paddle before the kayak, which gave me practice with the hand plane and extra motivation for my kayak project, because what’s the point of a paddle without a kayak?

At the beginning of the kayak build, I spent two to three hours in our local lumber store, Limback Lumber, picking out the perfect pieces of wood. For the gunwales I needed straight grain, clear (no knots), cedar boards. The grain on the edge of the board needs to be straight without running off the edges, otherwise the gunwales might split. My dad and I took out every single board that was the right size, laid them down, and scrutinized each one. 

For my ribs and coaming we ordered a special bamboo plywood (quarter inch, single layer, edge laminated, and carbonized) from Northwest Bamboo in Portland, Oregon.

It took an entire afternoon to mill the wood. We own a Milwaukee table saw and used it to rip the bamboo, the fourteen foot long cedar boards for the gunwales, stringers, and keel, and the thin cedar strips that we later laminated together to make the deck beams.

To make the forward deck beams I laminated five different layers of the cedar boards ripped to around an eighth of an inch thick. A mechanism called a laminating jig is a sheet of plywood with dowel pegs jammed into holes in a grid pattern. I smeared Gorilla glue in between the thin layers of cedar,  clamped the sheets together and wedged them around the pegs in a curve. The laminating jig braced each deck beam while the Gorilla glue cured.

I used a router for the first time to make the rib mortises. Then I pegged and lashed the ends of the gunwales together and fit the tenons on my deck beams into mortises along the gunwales. The deck beams and lashing turn the collection of cedar boards into a 2D shape.  

When I steamed the ribs and lashed on the keel and stringers the 2D shape became a 3D frame. Our rib steaming box is sketchy. Several times during the steaming process I had to tear a piece of Gorilla tape and plug a leak. Our steaming box is made of foam and connected to a large outdoor pressure cooker by a pipe. After filling the pressure cooker with water we set it on a propane burner to boil. The steam travels through the pipe and is sealed (hopefully) in the foam box where the bamboo pieces are resting. At timed intervals I put on my gardening gloves and slid one rib out at a time like steamed dumplings. As soon as each rib came out of the steamer I had to start bending, because if I waited too long it cooled and lost its pliability. If I bent too quickly, the bamboo snapped. After shaping each rib I squeezed the ends into the mortises on the gunwales and clamped them to stop the mortise splitting from the pressure of the rib. My boat has twenty ribs and the whole process took me about four hours. I broke three or four ribs during the process but luckily we had prepared extra rib stock.  

The stringers and keel stiffen the boat, give the hull its shape, and prevent the skin from touching the ribs. I clamped each stringer to the ribs on either side of the hull. Using artificial sinew, I repeated a lashing pattern around where the rib and stringer met, removing the clamps as I lashed. To attach the keel there is no accurate way to measure if it’s straight but Brian’s advice is to use your eye which, apparently, is accurate enough. I repeated the lashings on the keel, in total I did sixty lashings. 

One of the trickiest steps was making the coaming. I used another plywood, peg jig to clamp the bamboo to but it was hard to bend it to the right shape after it came out of the steamer and to manage the Gorilla glue and clamps while being careful not to snap the bamboo. I made my coaming at the same time as my brother, dad, and uncle and having four people made it easier.  

Sewing the skin transformed the frame into a hull. The kayak skin is made of a single piece of ballistic nylon, a strong woven fabric. I draped the fabric on the frame and pinned it tight using thumbtacks, as a dressmaker pins silk to a mannequin. I used a hot knife to cut off any excess material from where the two edges came together. After I pinned it, I used a zig zag stitch called a draw stitch to cinch the two edges together so I could stitch them up from the bow to the stern with a neat whip stitch. Once the rest of the boat was stitched up, I sewed in the coaming. I then sprayed the nylon with our garden hose before ironing it to shrink the skin and smooth out any wrinkles or puckers. I thought sewing up my boat was one of the most fun stages, although I injured my neck by doing too much in one go.  

Clear polyurethane protects and waterproofs the skin. To color it, I added burnt sienna and burnt umber powder pigment. I rolled three coats of the pigmented polyurethane onto the underside of my kayak (which was upside down). Then I flipped it over to paint the deck. I was slightly horrified to learn that in order to keep the bottom from smearing I needed to drill three small holes into the bottom of my kayak! The purpose of this is to create a tripod to keep the wet side from touching the saw horses. One screw goes in the keel at the bow and the other two go in the stringers at the stern. At the end I filled the holes with Aquaseal, a water sealing goop. While the coats were still wet I gently blew a heat gun over the surface from a few inches away. The hot air pops bubbles created by the roller and leaves a smooth, shiny finish. At first I didn’t like the color but then I realized that my kayak is the exact color of Madrona bark, and now after paddling my kayak and taking it on adventures, the color doesn’t feel so important to me any more. My boat took around two days to dry completely. The full project took two or three weeks of full time work and weighs almost exactly thirty pounds so I can carry it easily by myself. 

My skin-on-frame kayak is quiet on the water. While paddling I feel more part of the sea life around me and less like an intruder. Seals are curious and pop their heads up to watch me. On the day I first launched my kayak there was around fifteen knots of wind and the water was choppy and confused. Nevertheless, I felt stable and could control my bow even with the wind; and when we practiced capsizing and assisted rescues in Lake Washington, I had a hard time purposely flipping over. 

At the end of my kayak project, my family and I camped and kayaked for six days in the San Juan Islands. We started at San Juan County Park on the west coast of San Juan Island and paddled to Posey, Stuart, and Jones islands, in total around 40 miles including day trips. 

During the summer of Covid 19, I enjoyed getting up in the morning and having a project to work on until six in the evening. The kayak project gave each day a larger purpose. 

Brian Schulz

View posts by Brian Schulz
Hi, I'm Brian Schulz, owner and instructor for Cape Falcon Kayak. I've been teaching skin-on-frame kayak building for the last 14 years. I'm passionate about skin boat design and and helping people learn this amazingly easy and fun boat building system. My other passions include sustainable agriculture, natural building, and off-grid living.

1 Comment

  1. Steve Sempert
    November 9, 2023

    Congratulations on your beautiful build. I’m also building an F1 and will be using the NW bamboo kit and would really appreciate any info regarding steaming the ribs and coaming. Mostly whether you soaked any of them and what kind of steaming time you used.

    Thank you!

    Reply

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